The present invention relates generally to digital copy protection and more particularly to multiple key encryptions in highly distributed content delivery architectures.
Recent advances in the telecommunications and electronics industry, and, in particular, improvements in digital compression techniques, networking, and hard drive capacities have led to a growth in new digital services to a user's home. For example, such advances have provided hundreds of cable television channels to users by compressing digital data and digital video, transmitting the compressed digital signals over conventional coaxial cable television channels, and then decompressing the signals in the user's receiver. One application for these technologies that has received considerable attention recently includes video-on-demand (VOD) systems where a user communicates with a service operator to request video content and the requested content is routed to the user's home for enjoyment. The service operator typically obtains the content from an upstream market content provider, such as a content aggregator or distributor. The content aggregators, in this market stream, in turn, may have obtained the content from one or more content owners, such as movie studios.
While the video-on-demand market stream provides new opportunity for profits to content owners, it also creates a tremendous risk for piracy of the content. Such risk for piracy may arise at any place in the market stream that the content is exposed. Without appropriate protection, the content can be illicitly intercepted, stolen, copied, and redistributed, thus depriving content owners of their profits.
Current approaches to protecting the video content provide only partial or incomplete solutions. For example, many of today's implementation of digital rights management (DRM) systems restricts access to the video content to a specific hardware device. This reduces the flexibility and enjoyment of the video content by the user. It may also reduce the acceptance of such DRM implementations by the user.
Those DRM systems that do not lock viewing of the video content into a specific device often employ pre-encryption techniques that make it difficult to determine a source of unauthorized distribution of the video content in highly distributed systems.
Therefore, it is with respect to these considerations and others that the present invention has been made.